Is it my Timing Belt or Oil Sludge? What's the difference?

[rasczak]

Beginning to get nervous at the prospect of doing this on my own. 🙁 The write up LTC8K6 provided was great. I'm not a noob when it comes to auto repair, however, I've always left big jobs like this to the big boys. Unfortunately, due to budget issues (lack of funds) I've come to the conclusion I need to do this myself.

Before I get started on this, I wanted to pick your brains about what things I should look out for, organizational tips you may have and other advice you guys would be able to give. Should I look to replace other parts since i am already in the guts of the car, how should I determine what needs replacing and such.

Thanks again!
Joe

 

[BW86]

do a leak down test

 

[bruceb]

I disagree about a timing chain being less efficient than a timing belt. All you find on race engines are Chains, usually double roller type. They are bit nosier, but more reliable if you use steel tooth timing gears and not the nylon tooth crap some car makers use for quietness. Yes, they can and will stretch, but they should go double the life of a timing belt before needing attention.

Regarding what to change when doing the belt:

Belt, Belt Tensioner, Accessory Drive Belt, check drive belt tensioner
Water Pump, T-Stat, flush cooling system, radiator hoses, new coolant
change engine oil & filter. Get the shop manual and follow the instructions
carefully. Take your time. Be sure to properly line up all the marks and dots
on the camshaft / crankshaft as per the manual. You also need some gaskets
for Timing Cover, water pump, t-stat & maybe also the Valve cover. And you
will need a torque wrench. Maybe throw in new spark plugs.

 

[JulesMaximus]

I disagree about a timing chain being less efficient than a timing belt. All you find on race engines are Chains, usually double roller type. They are bit nosier, but more reliable if you use steel tooth timing gears and not the nylon tooth crap some car makers use for quietness. Yes, they can and will stretch, but they should go double the life of a timing belt before needing attention.

I said on an engine with overhead cams (or DOHC) it is less efficient because the chain has to be so long in comparison to pushrod engines. A long chain going over 2 or 4 overhead cams is going to add a lot of rotating mass, a belt would definitely reduce that quite a bit, thereby it is more efficient.

 

[Zenmervolt]

I said on an engine with overhead cams (or DOHC) it is less efficient because the chain has to be so long in comparison to pushrod engines. A long chain going over 2 or 4 overhead cams is going to add a lot of rotating mass, a belt would definitely reduce that quite a bit, thereby it is more efficient.

For a given strength, a chain is usually lighter than a belt as well as more compact. That's why sportbikes use chains for their final drive.

ZV

 

[Eli]

Chains stretch and the tensioners still fail 😉
I'd rather have a belt.

Screw that. I'm very thankful Honda built my Insight engine with a timing chain. I think it's practically the only newer Honda engine in existance that uses a chain.

AFAIK, they did it because they wanted to keep overall maintenance costs down. Being the 1st hybrid, people were worried about how long the batteries would last, and how expensive they would be to replace in the event of failure. Turned out to be a good decision, IMO.

 

[AsianriceX]

Screw that. I'm very thankful Honda built my Insight engine with a timing chain. I think it's practically the only newer Honda engine in existance that uses a chain.

I'm no Honda expert, but I think newer K series engines have timing chains.

OP, I wish you the best of luck in getting this fixed, but I believe the AEB 1.8t is an interference engine. If your belt broke during operation and you attempted to start it after that event, I can't imagine you not having any bent valves or other damage. 🙁

 

[exdeath]

I said on an engine with overhead cams (or DOHC) it is less efficient because the chain has to be so long in comparison to pushrod engines. A long chain going over 2 or 4 overhead cams is going to add a lot of rotating mass, a belt would definitely reduce that quite a bit, thereby it is more efficient.

For a given strength, a chain is usually lighter than a belt as well as more compact. That's why sportbikes use chains for their final drive.

ZV

There are also multiple small chains, so it's not like it has to be one large heavy duty chain. Each chain only has to deal with the tension/loading from it's independent assignment, so they can be smaller and lighter.

The DOHC 4.6 in my 03 Cobra uses 4 chains. One for each bank (offset on their own crank sprocket), and two tiny ones that connect the intake and exhaust cams.

Most OHC V engines are going to use independent chains per bank, just because you end up with a lot of wasted chain length and unnecessary idlers and tensioners and complexity to go down under the valley and double back up the other bank. Not to mention the chain has to be much bigger since a couple links would have to withstand the tension loads of the entire timing system with a single chain. Cheaper, easier, and more efficient to just run two chains. The heads are offset by the width of a connecting rod already anyway, perfect for offset chains.

 

[JulesMaximus]

There are also multiple small chains, so it's not like it has to be one large heavy duty chain. Each chain only has to deal with the tension/loading from it's independent assignment, so they can be smaller and lighter.

The DOHC 4.6 in my 03 Cobra uses 4 chains. One for each bank (offset on their own crank sprocket), and two tiny ones that connect the intake and exhaust cams.

Most OHC V engines are going to use independent chains per bank, just because you end up with a lot of wasted chain length and unnecessary idlers and tensioners and complexity to go down under the valley and double back up the other bank. Not to mention the chain has to be much bigger since a couple links would have to withstand the tension loads of the entire timing systems with a single chain.

And it costs a small fortune to rebuild that DOHC 4.6 engine in your Cobra. Just sayin' 😉

 

[exdeath]

And it costs a small fortune to rebuild that DOHC 4.6 engine in your Cobra. Just sayin' 😉

Oh yeah.... Fortuneately the timing system doesn't require maintenance. I had a erratic random tick I couldn't find for the longest time and dreaded it being a timing chain tensioner, it ended up being a blower rotor bearing that I got done along with a blower port for $500.

OHC engines have way more parts than pushrod engines contrary to what most people think. Just a timing / front cover set for the DOHC engine is like $600. 8 sprockets, 4 chains. 4 guides, 4 tensioners, etc. That's not even getting into the heads (32 lifters, roller followers, etc). 16 push rods are nothing.

And I long for the silky smooth sound of a timing belt sometimes. It took me a long time to just accept these are noisy engines with all those parts clicking around and stop being paranoid and trying to silence every little sound.

 

[exdeath]

Beginning to get nervous at the prospect of doing this on my own. 🙁 The write up LTC8K6 provided was great. I'm not a noob when it comes to auto repair, however, I've always left big jobs like this to the big boys. Unfortunately, due to budget issues (lack of funds) I've come to the conclusion I need to do this myself.

Before I get started on this, I wanted to pick your brains about what things I should look out for, organizational tips you may have and other advice you guys would be able to give. Should I look to replace other parts since i am already in the guts of the car, how should I determine what needs replacing and such.

Thanks again!
Joe

It's probably going to cost you the same. You are going to do an engine tear down and don't even know what tools you need? You'll probably end up spending just as much or more on tools you'll only use once as you would to pay someone to do it, quickly and right the first time. It takes a long time to build a collection of tools, and doing a lot of work more than just once in order for it to be cheaper to DIY. It's almost always more expensive when you are just starting out as you have to buy a few $100 in tools each time you need to do something new. That's something most people overlook when they think they can do it themselves and save some money.

example: changing your own oil the very first time will cost you over $100 for a jack, a pair of jack stands, drain bucket, socket/wrench set (you would buy at least a small set at that point, not just the 1 you need), etc. It would take you changing your own oil more than 5 times before it got down <= $20 like most shops would charge, and that's still not including the oil/filter cost.

Wanting to learn and all is great, and it can be quite rewarding, but don't mislead yourself with it being cheaper as a reason to do it yourself. It isn't in the short run.

 

[JulesMaximus]

Oh yeah.... Fortuneately the timing system doesn't require maintenance. I had a erratic random tick I couldn't find for the longest time and dreaded it being a timing chain tensioner, it ended up being a blower rotor bearing that I got done along with a blower port for $500.

OHC engines have way more parts than pushrod engines contrary to what most people think. Just a timing / front cover set for the DOHC engine is like $600. 6 sprockets, 4 chains. 4 guides, 4 tensioners, etc. That's not even getting into the heads (32 lifters, roller followers, etc). 16 push rods are nothing.

And I long for the silky smooth sound of a timing belt sometimes. It took me along time to just accept these are noisy engines with all those parts clicking around and stop being paranoid and trying to silence every little sound.

Dude, don't get me wrong, I love that engine and was looking at buying a slightly used 2003 Cobra Convertible with less than 10k miles a few years ago (well, 2004). It looked pristine and drove like it was brand new. I passed on it though...kind of wish I hadn't at times.

 

[rasczak]

It's probably going to cost you the same. You are going to do an engine tear down and don't even know what tools you need? You'll probably end up spending just as much or more on tools you'll only use once as you would to pay someone to do it, quickly and right the first time. It takes a long time to build a collection of tools, and doing a lot of work more than just once in order for it to be cheaper to DIY. It's almost always more expensive when you are just starting out as you have to buy a few $100 in tools each time you need to do something new. That's something most people overlook when they think they can do it themselves and save some money.

example: changing your own oil the very first time will cost you over $100 for a jack, a pair of jack stands, drain bucket, socket/wrench set (you would buy at least a small set at that point, not just the 1 you need), etc. It would take you changing your own oil more than 5 times before it got down <= $20 like most shops would charge, and that's still not including the oil/filter cost.

Wanting to learn and all is great, and it can be quite rewarding, but don't mislead yourself with it being cheaper as a reason to do it yourself. It isn't in the short run.

Thanks for the insight. I read up on link that was posted on the first page. I've got most of those tools (torx/allen wrenches, socket wrenches, Hydr. jack). The only thing I do not have is the Torque wrench. ( I could probably rent this at my local Autozone, it not I'll just buy one.) I've got nothing to lose at this point. I've freed up my next two weekends for this.

I got part estimates

**edited** Timing belt Kit http://www.passat-parts.com/18TBrokenTimingBeltKit.htm $215.00
water pump $50.00 (since I'm in there already)

For parts alone that's roughly $859.00 say $1000.00 for any uh-ohs vs. $3500 I was quoted. My time is valuable, yes, but, if I can save myself $2700.00 I'm going to do it. Even if I have to learn on the fly. If it doesn't work out, then c'est la vie. I'll part it out, ebay the stuff that I bought for 15&#37; markdown, then junk the rest of the car. Isn't working on your own car to save money the reason most of you do it as well? 😉

 

[Lotheron]

Thanks for the insight. I read up on link that was posted on the first page. I've got most of those tools (torx/allen wrenches, socket wrenches, Hydr. jack). The only thing I do not have is the Torque wrench. ( I could probably rent this at my local Autozone, it not I'll just buy one.) I've got nothing to lose at this point. I've freed up my next two weekends for this.

I got part estimates

Timing belt Kit $259.00
new cylinder head (if machine shop is too expensive) $550.00
water pump $50.00 (since I'm in there already)

For parts alone that's roughly $859.00 say $1000.00 for any uh-ohs vs. $3500 I was quoted. My time is valuable, yes, but, if I can save myself $2700.00 I'm going to do it. Even if I have to learn on the fly. If it doesn't work out, then c'est la vie. I'll part it out, ebay the stuff that I bought for 15% markdown, then junk the rest of the car. Isn't working on your own car to save money the reason most of you do it as well? 😉

So did you find out for sure if your engine was interference? If so possibly add valves, possibility pistons/rings/ring compressing tool.

 

[bruceb]

He is pricing in the cost of a replacement head for the engine (which he probably will not need)

 

[rasczak]

So did you find out for sure if your engine was interference? If so possibly add valves, possibility pistons/rings/ring compressing tool.

ahhh yes. It is interference. I am doing the tear down this weekend to verify what parts aside from the timing belt I will need. I am almost certain I will need new valves, possibly new lifters. I will check the pistons as well. If I have to go that far into the engine, I'm not going to waste anymore time or money on it and part it out. I don't want to get into doing a complete rebuild as I just don't have the time or resources for that big of a job.

 

[rasczak]

He is pricing in the cost of a replacement head for the engine (which he probably will not need)

You're correct. I actually found a timing belt kit with valves instead for $215 included are head gasket, valves and bolts.

 

[Lotheron]

He is pricing in the cost of a replacement head for the engine (which he probably will not need)

I was wondering about this my self, but then I thought VW had some weird engineering on this that would damage the head to. At most it should be valves/lifters/pistons. Oh and gaskets and seals (new head gasket, etc)

Or part the car out 🙂

 

[Lotheron]

You're correct. I actually found a timing belt kit with valves instead for $215 included are head gasket, valves and bolts.

Obviously aimed at those in your situation. 🙂

 

[rasczak]

Obviously aimed at those in your situation. 🙂

hehe that it is. 😉

 

[exdeath]

Might be cheaper and definately easier to just buy a used engine from a wrecker and core the old one if the damage is extensive.

 

[AsianriceX]

Bump for update!